Pump



May 27, 1924. 1,495,419

1 M. 5. GRol-l PUMPA Filed Feb. s, 1922 fmt/"en taza v Patented ay 2'?, i924.

' attain eran "ri- PUMP.

Application led February 3, 1922. Serial No. 533,906.

To aZZ whom tf/nay concern.'

Be it known that I, MELVIN SOLOMON GROH, a resident Vof the city Of-Toronto,

in the county of York, in the Province ot Ontario, Canada, have invented certain'new and useful Improvements in Pumps, of which the following is the specification.

My invention relates to improvements in pumps and the object of the invention is to devise a pump particularly designed to pump back the refrigerant gases into the -condensingchamber of the refrigerator system.

A further object is to construct a pump that. will be more simple than those at present in use and which will have a fewer number of parts.

A still further object is to devise a pump in which there will be an ellective oil seal for the gas when being pumped therethrough.

My invention consists of a pump constructed vand arranged all as hereinafter more particularly described and illustrated in the accompanying drawing in which- Fig. 1 represents a side elevation of a pump constructed according to my invention.

Fig. 2 'is an elevational view of the other side of the pump.A

'Fig 3 is a vertical section through the line 3--3 Figure 7. y

Figpf is a vertical section through the line 4-4 Figurep 3.

' Fig. 5 is a vertical section through the line 5-5 Figure 3.

Fig. 6 is a vertical sectionthrough the line 6-6 Figure 3,showing the Outer meshin'gspiral gears removed.

ig. 7 is a similar view to Figure 6 showin the spiral gears in place, and

ig. 8 is an end view.

Like characters of reference indicate corresponding p'arts in the different views.

1 is a portion of the pump casing which is illustrated and described in my cO-pending application for improvements in refrigerating machines Serial Number 533,905, filed Feb. 3, 1922, as the cover plate of the pump and condensingchambers, said portion 1 having an inwardly extending annular boss 2. 3 is a bearing plate registeru ing therewith.l 4 is a second bearingplate. 5 and 6 are interrneshing spirally cut gears journalled by means of the spindles 7 and 8 respectively in the bearing' plates 3 and 4. The outer spindle 8 is extended through a stuffing box-9 exterior-ly of the portion ofv the casing 1 and is adapted to be driven.

by any 'suitable means. Thus the gear 6 becomes the driving gear and the gear 5 the driven gear.

The bearing plate 3 is provided with a semicircular housing 31 extending about the gearsA 5 and 6, the interior of the said housing being suitably curved to partiahll encase each'of the gears, said interior wall of the housing engaging the crowns lof the gear teeth. The bearing plate 4 is secured to the bearing plate 3 and the portion of th casing 1 by means of the screw bolts 10.

11 is the gas inlet in the casing 1, the inner end of thesaid inlet registering with the inlet port 12 extending through. the

bearing plate 3 and so positioned as to communicate with the gears at a point on the housing side of the vertical centre line y through the pump.

13 is an oil feed pipe communicating with the Oil inlet ports 14 in the inner face of the bearing plate 3fthrough the medium ,of the slots 15 in the inner face 4of the boss 2 of thecasing portion 1.

The gears 5 and 6 are so mounted that the teeth "engage each other first on the intake end. "uiGonsequently as they are rotated'past the-inlet-port`12 there will be a space betweenthe root -Of the toothon one gear and the corresponding crown on the other.

Owing to the' vfact that the gears are spiral- -ly .-ciitsuch-space will gradually enlarge as the gears rotate further and conseguently the gas from the intake port will space. l

As the gears rotateffurtherthe crown of v each tooth will engage the inner wall of the housing 31 and thus pocket thegas in the spaces between the teeth. l

As the gears are rotated past lthe o il inle ports 14 the Oil will be forced into the spaces etween the teeth, and as itis Aunder considerable As the teeth revelve further their crowns ll this f pressure' will compress the gas will disengage from the interior wall oit the housing 3l and permit the gas in the spaces between the teeth to unite with the gas in the casing, which will be facilitated owing to the conned gas in the spaces between the teeth of the gear, prior to release into the casing being compressed by the introduction of the oil under pressure into such spaces to a pressure equal to the 'gas in the casing.'

rlhe pump is or" course designed to be situated in a gas tight chamber.

. As the gears revolve the majority of the oil which has been introduced into the spaces betweenthe teeth is thrown otli1 leaving a thin 'film on the teeth thereon which acts as an oil seal when the spaces between such teeth again receive a further supply o'f gas.

lin order to avoid gas pocketing, as the teeth reach the vertical centre line of the pump an aperture 16 is provided in the inner bearing plate 4e. As the spiral gears rotate sich gas is squeezed between the teeth ifroml the intake port end towards the inner bearing plate end, and consequently passes through the aperture 16 in such plate al.

From the above description it will be seen that l have devised a simple and etective pump which while particularly designed for pumping refrigerant' gases can at the same time be -used tor pumping other gases, air or certain liquids izt so desired.

Further ll have devised a pump of the class described which will have comparatively few parts in comparison with such pumps at present in use.

`-What l claim as my invention is:

l. ln a pump, the combination with thoe pump chamber casing, of intermeshing spirally cut gears, means for introducing the pumped iluid directly intocthe spaces between the intermeshing teeth at one end oztY the gears in a direction substantially parallel to the axes of such gears and means :tor sealing the fluid in the spaces between the teeth vof the gears for a part ot a revolution thereof.

2. ln a pump, the combination with the pump chamber casing, orn intermeshing spirally cut gears, means for introducing the pumped fluid directly into the spaces between the intermeshing teeth at one end of the gears in a direction substantially parallel to the axes of such gears, means for sealing the lluid in the spaces between the teeth ot the gears for a part of a revolution thereof and means for introducing a sealing medium under 'pressure into the spaces between the teeth at af predetermined point during the revolution of each gear.

3. ln a pump, the combination with the pump chamber casing, of intermeshing spirally cut gears, means ltor introducing the pumped luid into the spaces between the intermeshing teeth at one end ot the gears,

means tor sealing the :duid in the spaces between the teeth (-f the gears for a part of a revolution thereof and means tor releasing the pumped lluid from the spaces between the teeth of the gears prior to such teeth )1n- 1 termeshing.

t. ln a pump, the combination with the pump chamber casing having a duid inlet in the inner face thereof, of inner and opter spaced apart bearing plates suitably secured to the casing, one of the bearing plates having a fluid inlet port registering with the inlet in the casing, intermeshing spirally cut gears journalled between the bearing plates, 4

the inner face thereof, of inner and outer spaced apart bearing plates suitably secured to the casing, one ot the bearing plates havm ing a tluid inlet port registering with the inlet in the casing, intermeshing spirally cut gears journalled between the bearing plates, said inlet port in the bearing plate so positioned with respect to the gears that the fluid to be pumped is admitted directly into the increasing spaces between the teeth as they disengage, means for driving one of the gears, means for engaging the crowns or" the teeth of both gears during an equal part of their rotation from their point of disengagement with each other and means for sealing the spaces between the teeth of both gears during that part of their rotation in which the crowns of the teeth are engaged.

6. ln a pump, the combination with the pump chamber casing having a fluid inlet in the inner face thereof, of inner and outer spaced apart bearing plates suitably secured to the casing, one of the bearing plates having a fluid inlet port registeringr withv the inlet in the casing. intermeshing spirally cut gears journalled between the bearing "l plates, means for driving one of the gears. a segmental housing extending between the bearing plates and its inner wall consisting of two are shaped portions struck on radii substantially equal to the radii of the gear si: be

tion and the vertical centre line of the pump.

7. In a pump, the combination with the pump chamber lcasing having a lluid inletl in the inner face thereof, of inner and outer spaced apart bearing plates suitably secured to the casing, one of vthe bearing plates havingA a fluid inletV port registering with the inlet in the casing, intermeshing spirally cut gears journalled between the bearing plates, means for driving one of the gears,` a segmental housing extending between the bearing plates and its inner wall consisting of two arc shaped portions struck on radii substantially equal to the radii of the gear teeth crowns, the adjacent ends of the arc-shaped inner wall portions of. the housing constituting an inwardly extending pointed portion engaging the crowns of the gear teeth on-the inlet side of such gear, and the fluid inlet port in the bearing plate positioned on the horizontal centre line of the pump between the apex of the pointed portion and the vertical centre line of the pump the casing and adjacent bearing plate having sealing inlet passageways,therethrough terminating'in ports in the inner face :of such bearing platepositioned so as to admit the sealing l'uid to the spaces between the teeth of the gearing during the portion oftheir revolution that they are in contact with the housing. A

8.'In a pump, the combination with the pump rchamber casing having a fluid inlet in the inner face thereof, of inner and outer spaced apart bearing plates suitably secured to the casing, one of the bearing plates hav-- ing a fluid inlet'port registering with the inlet in the casing, intermeshing spirally cut gears journalled between the bearing plates, means for driving one of the gears, a segmental housing extending between the bearing plates and the interior wall thereof engaging the crowns of the teeth of both gears, the registering inlet in the casing and inlet port in the outer bearing plate being positioned on the horizontal longitudinal axis ofthe pump and on the housing side of the vertical longitudinal axis, the inner face of the casing having sealing fluid` inlets registering with ports in the outer bearingl plate. the. centre` of such ports being positioned on the pitch circles of the respective gear teeth.

9; In a pump, thel combinationl with thepump chamber casing, of intermeshing spirally cut gears, means for introducing the refrigerant fluid when in the gaseous state into the spaces between the teeth as they disengage from each other, means for .retaining Ithe gas in such spaces for a part of the. revolution of each gear, means for introducing a sealing fluid under ressure into the gas lled spaces between tlie teeth in a direction substantially parallel to the axes of the' gears, whereby the gas is compressed and sealed therein.

1.0., Ina pump, the combination with the pump chamber casing, of intermeshing spirally cut gears, means for introducing the refrigerant fluid 'when in the gaseous statev into the spaces between the teeth as they kdisengage from each other in a direction substantially parallel to the axes of such gears, means for retain-ing the gas in such space for a part of the revolution ofI each gear, means for introducing a sealing fluid under pressure into the gas filled spaces between the teeth in a direction substantially parallel to the axes of the gears, whereby the gas V,is compressedand sealed therein.

11. In a pump, the 'combination with the pump chamber casing, y of intermeshing spirally cutv gears, means for introducing the refrigerant fluid in the gaseous state.

into the spaces between the teeth of the gears as they disengage, means for compressing the gas 'in such spaces, means forV subsequently releasing the gas into l'the pump chamber, and means for expelling any gas in the spaces between the teethA inthe pump chamber prior to the teeth intermeshing again.

12. In a pump, the combination with the .pump chamber casing, of intermeshing sov spirally cut gears, means for introducing'- ythe refrigerant fluid when in a gaseousv state linto the spaces4 between-the teeth as they disengageffrom each other, means for retaining the gas -in such spaces for a part of the revolution of each gear, means for introducing a sealing fluid under ressure into the gas lled spaces between t e teeth whereby the gas is compressed and sealed, means for discharging thel gas from the spaces .between the teeth into the pump chamber casing, means for discharging the sealing fluid from the spaces between the teeth under centrifugal force into the pump chamber casing A,in a direction substantially at right angles to the axes of such gears.

14. In a pump, thecombination with a pump chamber casing, fof 'intermeshing `spirally -cut gears, `means-fer introducing the refrigerantiluid when in ai gaseous` state intov the spaces between the teeth as they disengage froml each other, means forv retaining the gas lin such spaces for a part'of the revolution @teach geen-means oi inseeiihg fluid from the 'spacesy between the trodueing e sealing Huid under pressure into teeth under centriugel force iiito the pump the gas illed spaces between the teeth chamber easing in e direction substamtieiiy whereby the ges is compressed and sealed, at right angles to the axes ofsuch gears end 5 means for discharging the gas from the prior to such teeth intermeshing again.

spaces between the teeth into the pump chamber casing, means -for discharging the l MELVN SLMQN GRH, 

